SV-1 Bandar

[Jeremy]

SV-1 Bandar, Laksmanavati Survey ship, laid down 1912

The Bandar ships were nominally "survey ships" but were intended as multi-role ships. Although quite old by the mid-1930s, they were the only ships besides the MS-8 minesweepers that could serve as ocean-going escorts. Their high speed and large amount of flexible displacement could see the six remaining ships refitted as ASW boats.

Displacement:
        730 t light; 758 t standard; 901 t normal; 1,015 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
        (213.81 ft / 206.69 ft) x 29.53 ft x (10.50 / 11.49 ft)
        (65.17 m / 63.00 m) x 9.00 m  x (3.20 / 3.50 m)

Armament:
      1 - 4.33" / 110 mm 45.0 cal gun - 40.96lbs / 18.58kg shells, 250 per gun
          Quick firing gun in deck mount, 1912 Model
          1 x Single mount on centreline, forward deck forward
      4 - 1.57" / 40.0 mm 39.0 cal guns - 1.85lbs / 0.84kg shells, 900 per gun
          Anti-air guns in deck mounts, 1912 Model
          1 x Twin mount on centreline, forward deck forward
                1 raised mount
          1 x Twin mount on centreline, aft deck aft
                1 raised mount
      4 - 0.47" / 12.0 mm 90.0 cal guns - 0.07lbs / 0.03kg shells, 2,000 per gun
          Machine guns in deck mounts, 1912 Model
          4 x Single mounts on sides, evenly spread
      Weight of broadside 49 lbs / 22 kg

Armour:
   - Gun armour:        Face (max)      Other gunhouse (avg)    Barbette/hoist (max)
        Main:   0.98" / 25 mm         -                       -
        2nd:    0.79" / 20 mm         -                       -

Machinery:
        Oil fired boilers, steam turbines,
        Direct drive, 2 shafts, 4,624 shp / 3,450 Kw = 19.98 kts
        Range 8,000nm at 10.00 kts
        Bunker at max displacement = 258 tons

Complement:
        81 - 106

Cost:
        £0.054 million / $0.216 million

Distribution of weights at normal displacement:
        Armament: 9 tons, 1.0 %
           - Guns: 9 tons, 1.0 %
        Armour: 4 tons, 0.4 %
           - Armament: 4 tons, 0.4 %
        Machinery: 184 tons, 20.5 %
        Hull, fittings & equipment: 323 tons, 35.9 %
        Fuel, ammunition & stores: 171 tons, 19.0 %
        Miscellaneous weights: 210 tons, 23.3 %
           - Hull above water: 60 tons
           - On freeboard deck: 90 tons
           - Above deck: 60 tons

Overall survivability and seakeeping ability:
        Survivability (Non-critical penetrating hits needed to sink ship):
          1,641 lbs / 744 Kg = 40.4 x 4.3 " / 110 mm shells or 0.8 torpedoes
        Stability (Unstable if below 1.00): 1.12
        Metacentric height 1.0 ft / 0.3 m
        Roll period: 12.4 seconds
        Steadiness      - As gun platform (Average = 50 %): 72 %
                        - Recoil effect (Restricted arc if above 1.00): 0.09
        Seaboat quality  (Average = 1.00): 1.80

Hull form characteristics:
        Hull has a flush deck,
          a normal bow and a cruiser stern
        Block coefficient (normal/deep): 0.492 / 0.507
        Length to Beam Ratio: 7.00 : 1
        'Natural speed' for length: 14.38 kts
        Power going to wave formation at top speed: 62 %
        Trim (Max stability = 0, Max steadiness = 100): 40
        Bow angle (Positive = bow angles forward): 10.00 degrees
        Stern overhang: 3.94 ft / 1.20 m
        Freeboard (% = length of deck as a percentage of waterline length):
                                Fore end,        Aft end
           - Forecastle:        20.00 %,  18.04 ft / 5.50 m,  13.12 ft / 4.00 m
           - Forward deck:      50.00 %,  13.12 ft / 4.00 m,  13.12 ft / 4.00 m
           - Aft deck:  15.00 %,  13.12 ft / 4.00 m,  13.12 ft / 4.00 m
           - Quarter deck:      15.00 %,  13.12 ft / 4.00 m,  13.12 ft / 4.00 m
           - Average freeboard:         13.52 ft / 4.12 m

Ship space, strength and comments:
        Space   - Hull below water (magazines/engines, low = better): 78.0 %
                - Above water (accommodation/working, high = better): 124.6 %
        Waterplane Area: 4,037 Square feet or 375 Square metres
        Displacement factor (Displacement / loading): 149 %
        Structure weight / hull surface area: 40 lbs/sq ft or 196 Kg/sq metre
        Hull strength (Relative):
                - Cross-sectional: 0.84
                - Longitudinal: 6.11
                - Overall: 1.03
        Excellent machinery, storage, compartmentation space
        Excellent accommodation and workspace room
        Ship has slow, easy roll, a good, steady gun platform
        Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Fittings:
-1 t: 1918 fire control (above deck)
-25 t: L/R wireless (above deck)
-10 t: Night fighting doodads (above deck)
-60 + 90 t: Survey facilities & equipment (hull + on deck)
-24 t: Weight reserve (above deck)